The expression originated from the Hebrew phrase
"azov oti be-ima shcha".
The origin of that Hebrew phrase
is probably "azov oti le-ma'an hashem!" which means "Leave me alone, for Christ / heavens sakes!"
it went certain
changes to "azov oti be-shem elohim" (Leave me alone, in the name of god!). Because the last sentence obviously
wishing that person to go away, it evolved into a less crule manner "azov oti be-ima shkca" - "Leave me in your mother".
expression is useable whenever you don't have
the patience for someone
or for an idea.